PEORIA, Ariz. -- Sean Manaea overpowered the Cape Cod League to such an extent during the summer of 2012 that he thrust himself into the race to go No. 1 overall in the 2013 Draft. But he injured his hip as a junior at Indiana State and wasn't the same guy, though the Royals still bought into his Cape dominance enough to give him a supplemental first-round record $3.55 million as the 34th overall pick.

Manaea, Oakland's No. 3 prospect, has had plenty of success in pro ball, leading the high Class A Carolina League in strikeouts in his 2014 pro debut and recording a 1.90 ERA at Double-A Midland this summer after going to the Athletics in the Ben Zobrist trade. But the left-hander still hasn't recaptured the stuff he had on the Cape, where he sat at 94-96 mph and touched 98 with his fastball while flashing a plus slider and solid changeup.

Making his second start of the Arizona Fall League for the Mesa Solar Sox on Wednesday, Manaea came out throwing 92-94 in the first two innings but worked at 90-92 in the next two. With the crossfire in his delivery and low three-quarters arm slot, he did generate run and sink and threw 30 of 43 fastballs for strikes.

However, Manaea's fastball resulted in nearly as many hits (four) as swing-and-misses (five). While the Peoria Javelinas couldn't square them up easily, his heaters also couldn't put anyone away besides Tyler O'Neill (Mariners), who whiffed on 94- and 91-mph pitches.

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Manaea's slider was more sweepy than biting, ranging from 79-81 mph. Only 10 of his 20 sliders earned strikes, though he did get D.J. Peterson (Mariners) and Nick Torres (Padres) to chase breaking balls out of the strike zone for two of his four whiffs. Five of his nine changeups found the zone and the pitch was a bit firm, usually arriving at 84-85 mph and with just ordinary fade.

Scouts question whether Manaea has enough athleticism to maintain his velocity and command his pitches well enough to be a starter. Those looked like legitimate concerns on Wednesday, when he gave up seven baserunners and three runs in four innings of work.

Peoria starter Nick Travieso, Cincinnati's No. 6 prospect, outshone Manaea, facing just 10 batters in three hitless innings. He has yet to advance past high Class A three years in four pro seasons since the Reds made him the 14th overall pick in the 2012 Draft, but he displayed premium velocity against the Solar Sox.

Travieso's opening pitch of the game hit 95 mph and he registered 96 six times in the first inning. All eight of his fastballs in his third and final inning reached 94 or 95 mph.

Travieso didn't need a lot of effort to generate velocity and his fastball featured some armside run. He showed some ability to hit both corners, though there also were times where his heater tailed off the right side of the plate. All told, he threw 22 of 35 fastballs for strikes, generating four empty swings and eight called strikes.

Top Prospects: Travieso, CIN

Top Prospects: Nicholas Travieso, RHP, Reds

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As impressive as Travieso's fastball was, his cutter was more effective. It ranged from 85-90 mph and its combination of velocity and movement gave Mesa fits. He threw six cutters, four for strikes -- three swings-and-misses (including whiffs of the Angels' Caleb Adams and the Athletics' Jaycob Brugman to finish his outing) and a harmless pop-up to shortstop.

Travieso also mixed in three 79-82 mph sliders and once 87 mph changeup. The only batter to reach against him was Casey Gillaspie (Rays), who worked a full-count walk off him in the second inning, and Travieso fanned four Solar Sox.

Willson Contreras, the Cubs' No. 10 prospect, was the most impressive hitter in Peoria's 5-3 victory, doubling twice and homering in four at-bats. After Travieso induced him to hit an easy comebacker with a 95-mph fastball in the first inning, Contreras drove an 89-mph fastball down and in to left-center in the fourth against Mariners left-hander Ryan Horstman and then took an 87-mph heater in the same location to the right-field wall in the seventh off Orioles sidearming southpaw Donnie Hart.

Top Prospects: Contreras, CHC

Top Prospects: Willson Contreras, C, Cubs

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Braves right-hander Mauricio Cabrera entered in the eighth inning and fired 99-102 mph fastballs to the first three hitters. Up came Contreras, who was hunting fastballs and got badly fooled when Cabrera took something off and started him with an 89-mph pitch in the dirt. When Cabrera tried to do the same thing three pitches later, he hung an 89-mph offering and Contreras crushed it over the fence in left-center.

Originally signed as a third baseman out of Venezuela in 2009, Contreras converted to catcher in 2012 and emerged as one of baseball's best prospects at the position this year. He led the Double-A Southern League with a .333 average this year, thanks to a quick right-handed swing and an improved approach at the plate. He's also a capable defender with solid arm strength, though he didn't display his defensive ability on Wednesday because he was DHing.